Existing technology is capable of producing methanol from methane and carbon dioxide, however it is a long, tedious and expensive undertaking. Multiple reactions are required for which dedicated equipment is needed. Like many organic preparations, conversions are low and repeated separations are involved. At the heart of the process is the generation of synthesis gas with all that such chemistry implies: high pressure, elevated temperatures and finicky catalysts.
To illustrate the known procedures for producing methanol, the following equations are helpful.CO2+3 H2→CH3OH+H2O  1.CH4+H2O→CO+3 H2  2.
Equation no. 1 represents the classical reaction for producing methanol from synthesis gas. The reaction requires moderate temperature, high pressure and a catalyst based on a copper-zinc compound.
Equation no. 2 shows the formation of synthesis gas by methane steam reforming. High temperatures are required as well as a catalyst typically comprising nickel.
When equations 1 and 2 are combined, the following relationship is obtained.CH4+CO2→CH3OH+CO  3.
The expression represents the goal of the exercise, namely, the production of methanol from methane and carbon dioxide. Nevertheless, the procedure is indirect and necessitates substantial investment.
Because widespread recovery of carbon dioxide is not practiced, a source of oxygen is required for current operations. Thus, air separation units are needed to provide oxygen to existing methanol facilities. This requirement presents an added cost.
As priorities begin to shift toward more environmentally friendly practices, carbon dioxide will likely assume greater attention. Its recovery and disposition may become mandatory. With this trend in mind, there is an incentive to develop improved technology for the production of methanol using carbon dioxide as a feedstock. This and other objectives of the present invention will become apparent from the discussion that follows and the illustration therewith.